Per-Olof Åstrand — Swedish pioneer of exercise physiology

Per-Olof Åstrand (1922–2015), Swedish physiologist and educator, developed influential methods for measuring aerobic fitness and helped establish modern exercise physiology as a scientific discipline.

Overview

Per-Olof Åstrand (21 October 1922 – 2 January 2015) was a Swedish professor and researcher in human physiology. He is widely regarded as a pioneer in the scientific study of physical work, fitness and endurance. Åstrand combined laboratory measurement with simple field methods to make exercise science practical for clinicians, coaches and occupational health professionals.

Career and appointments

Åstrand held positions at the Royal Gymnastic Central Institute (GCI/GIH) in Stockholm during the 1970s and later worked at the Karolinska Institutet from 1977 until 1988. He served as a member of the Nobel Assembly at Karolinska Institutet and spent most of his career based in Sweden, where his teaching and textbooks influenced generations of physiologists and physical educators.

Main contributions

Åstrand helped formalize methods to estimate aerobic capacity (VO2 max) and to assess cardiovascular responses to exercise. His work emphasized reproducible protocols, measurement of heart rate and oxygen consumption, and translating laboratory findings into routine tests. Two of his best-known legacies are a submaximal cycle ergometer protocol and an associated nomogram used to predict maximal oxygen uptake from steady-state heart rate.

Methods and practical tools

Submaximal cycle ergometer testing: allows estimation of aerobic capacity without requiring a maximal effort.
Åstrand nomogram and tables: graphical aids that translate submaximal heart rate and workload into estimated VO2 max.
Textbooks and protocols: clear, practicable guidance for laboratories, clinics and sports programs.

Significance and legacy

Åstrand's approaches made assessment of cardiorespiratory fitness accessible beyond specialized research centers. His methods remain taught and adapted in sports science, clinical exercise testing and occupational health. He is often described as a "legend" and one of the founding figures of modern exercise physiology. His influence persists through continued use of his tests, teaching materials and the many scientists he trained.